U.S. patent application number 14/076028 was filed with the patent office on 2014-08-07 for intragastric implant devices.
This patent application is currently assigned to IBIS Medical, Inc.. The applicant listed for this patent is IBIS Medical, Inc.. Invention is credited to Jaime Vargas.
Application Number | 20140221899 14/076028 |
Document ID | / |
Family ID | 44673678 |
Filed Date | 2014-08-07 |
United States Patent
Application |
20140221899 |
Kind Code |
A1 |
Vargas; Jaime |
August 7, 2014 |
INTRAGASTRIC IMPLANT DEVICES
Abstract
An intragastric anchor implant device is provided with a
substantially rigid member having proximal and distal ends and
atraumatic tips or features disposed near the proximal and distal
ends. The atraumatic features prevent damage to the tissues of the
stomach and the gastrointestinal track and may help to anchor the
device in the stomach, while the substantially rigid member resists
bending so as to engage a tissue of the stomach or the
gastrointestinal tract to prevent passage through the stomach. The
anchor implant device is coupled with a therapeutic device,
typically a sleeve, such as an intestinal bypass sleeve. Ideally,
the device includes a sliding seal to direct a flow of food
particles from the stomach through the sleeve, so as to be useful
in treating a disorder, including obesity and diabetes. Methods of
deploying the anchor implant devices are also disclosed.
Inventors: |
Vargas; Jaime; (Redwood
City, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
IBIS Medical, Inc. |
Redwood City |
CA |
US |
|
|
Assignee: |
IBIS Medical, Inc.
Redwood City
CA
|
Family ID: |
44673678 |
Appl. No.: |
14/076028 |
Filed: |
November 8, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
13073762 |
Mar 28, 2011 |
8597224 |
|
|
14076028 |
|
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|
61317710 |
Mar 26, 2010 |
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Current U.S.
Class: |
604/8 |
Current CPC
Class: |
A61F 5/0076
20130101 |
Class at
Publication: |
604/8 |
International
Class: |
A61F 5/00 20060101
A61F005/00 |
Claims
1. A method for treating a patient having a metabolic related
disorder, said method comprising: deploying an implant within a
gastrointestinal tract of the patient so that a proximal end of an
anchor of the implant is disposed within a stomach of the patient,
the anchor having a proximal atraumatic feature at the proximal end
and a distal atraumatic feature at a distal end with an elongate
element extending therebetween; supporting a sleeve of the implant
with the anchor so that the sleeve extends along an intestine of
the patient, and so that a flow including ingested matter enters a
lumen of the sleeve from the stomach, the flow being in contact
with a wall of the stomach; inhibiting advancement of the anchor
around a bend of the intestine near the stomach by engaging a
proximal portion of the anchor against a surface area of a mucosa
of the stomach, by engaging a distal feature of the anchor against
a surface area of the gastrointestinal tract distal of the mucosal
surface area and by resisting bending of the elongate element
between the proximal and distal ends; advancing the flow along the
intestine within the lumen of the sleeve, the ingested matter
comprising ingested nutrients and particles of food.
2. The method of claim 1, wherein the flow further comprises
stomach secretions.
3. The method of claim 1, wherein the proximal portion of the
anchor comprises the proximal atraumatic feature.
4. The method of claim 1, wherein engagement of the surface areas
with the proximal and distal portions of the anchor substantially
limits the displacement of a longitudinal axis of the anchor so as
to maintain a position of the anchor within the stomach and to
prevent passage of the anchor through the gastrointestinal
tract.
5. The method of claim 1, wherein the sleeve comprises an
intestinal bypass sleeve having a lumen extending between a
proximal opening and a distal opening, wherein the sleeve comprises
a material substantially impenetrable to the flow of the ingested
matter advancing therethrough when the ingested matter enters the
sleeve from within the stomach and advances along the lumen of the
sleeve so as to inhibit contact of the flow with an intestinal wall
along the sleeve such that the disorder is mitigated.
6. The method of claim 5, wherein the disorder comprises diabetes,
and wherein the sleeve is substantially impenetrable to chyme
advanced through the lumen of the sleeve so as to inhibit
production of a hormone affecting the diabetes.
7. The method of claim 5, wherein deploying the implant is
performed such that the anchor extends across the pyloric valve
such that the distal end of the anchor is positioned distal of the
pyloric valve in a proximal portion of the duodenum and the
proximal end of the anchor is positioned in the stomach, the
gastrointestinal surface area comprising a lumenal area of the
duodenum.
8. The method of claim 7, wherein the elongate element between the
ends has a profile smaller than the sleeve, and further comprising
radially supporting the proximal opening of the sleeve with the
distal feature of the anchor, wherein the distal feature extends
laterally from the elongate element of the anchor to the sleeve so
that a majority of the flow advances around the elongate element
and through the pyloric valve, and enters the proximal opening and
advances within the sleeve.
9. The method of claim 8, wherein the distal feature comprises an
array of projections extending radially between the elongate
element and the proximal opening, and wherein the projections
compliantly deflect within the gastrointestinal tract so to spread
anchoring loads across the area of the duodenum.
10. The method of claim 9, wherein the anchoring loads are forces
exerted on the anchor by a tissue of the stomach or
gastrointestinal tract substantially imparted by gastric
motility.
11. The method of claim 8, wherein the distal feature comprises a
plurality of flexible struts, and wherein the struts compliantly
deflect within the gastrointestinal tract while urging the proximal
opening of the sleeve radially outwardly toward the surrounding
duodenum.
12. The method of claim 5, wherein deploying the implant is
performed such that a distal end of the anchor is positioned within
the stomach proximal of the pyloric valve and the proximal end of
the anchor is positioned in the stomach.
13. The method of claim 12, further comprising: expanding the
distal atraumatic feature so as to increase a profile of the distal
feature so as to prevent passage of the distal feature across the
pyloric valve.
14. The method of claim 5, wherein supporting the sleeve comprises
axially restraining the sleeve with a flexible connector extending
distally from the anchor toward the sleeve, and radially supporting
the proximal opening of the sleeve with a compliant coupling
support extending laterally from the flexible connector, and
wherein deploying the implant comprises positioning the sleeve so
that the proximal opening is located in the duodenum,
15. The method of claim 5, wherein the implant includes a sliding
seal circumscribing the proximal opening of the sleeve, and wherein
positioning the sleeve comprises positioning the sliding seal in a
proximal portion of a duodenum of the patient to sealingly engage
an inner wall of the duodenum so as to direct the flow from the
stomach through the proximal opening into the lumen of the
sleeve.
16. The method of claim 5, wherein the implant includes a sliding
seal circumscribing the proximal opening of the sleeve, and wherein
positioning the proximal opening comprises positioning the sliding
seal in the antrum of the stomach to sealingly engage an inner wall
of the antrum so as to direct a fluid or solid flowing from the
stomach through the proximal opening into the lumen of the
implant.
17. The method of claim 1, further comprising radially constraining
at least one of the proximal feature or the distal feature in a
small profile configuration and releasing the at least one feature
to expand elastically radially outwardly into a large profile
configuration for use of the implant within the gastrointestinal
tract.
18. An implant for treating a patient having a metabolic related
disorder, said implant comprising: an anchor having an elongate
element extending between a proximal end and a distal end, a
proximal atraumatic feature disposed near the proximal end, and a
distal atraumatic feature disposed near the distal end; the
proximal atraumatic feature configured to inhibit tissue trauma
when urged against a surface area along a mucosa of a stomach of
the patient, the distal atraumatic feature configured to inhibit
tissue trauma when urged against a surface of a gastrointestinal
tract of the patient, and the elongate element being substantially
rigid so as to resist bending between the proximal and distal ends
and sufficiently long so that the anchor is configured to inhibit
advancement of the anchor around a bend of the intestine near the
stomach when under the anchoring loads; and an intestinal bypass
sleeve having a lumen extending between a proximal opening and a
distal opening, wherein the sleeve comprises a material
substantially impenetrable to a flow including ingested matter when
passed through the lumen, the flow of matter being in contact with
a wall of the stomach, the proximal opening supported distally of
the proximal end of the anchor so that the flow flows from within
the stomach into the lumen.
19. The method of claim 18, wherein the flow comprises chyme
including stomach secretions, ingested nutrients and food
particles, wherein the disorder comprises diabetes, and wherein the
sleeve is further substantially impenetrable to the flow and is
configured so as to inhibit production of a hormone affecting
diabetes within the intestine.
20. The implant of claim 18, wherein the distal feature is sized
and configured to be advanced through a pyloric valve of the
patient such that, when implanted, the distal end of the anchor is
distal of the pyloric valve in a proximal portion of a duodenum and
the proximal end of the anchor is in the stomach, the distal
surface area comprising a lumenal area of the duodenum.
Description
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] The present application is a continuation of U.S. patent
application Ser. No. 13/073,762, filed on Mar. 28, 2011, which
claims the benefit of U.S. Provisional Patent Application No.
61/317,710 filed on Mar. 26, 2010, each of which the entire
contents are incorporated herein by reference.
[0002] The present application is related generally to U.S. patent
application Ser. No. 12/568,899, filed on Sep. 29, 2009, entitled
Intragastric implant Devices."
FIELD OF THE INVENTION
[0003] The present invention relates generally to medical devices,
system and methods. Exemplary embodiments provide devices, systems,
and methods for anchoring a treatment or diagnostic device in the
stomach of a patient. Specific embodiments provide devices,
systems, and methods for anchoring a therapeutic device in the
stomach of a patient for the treatment of obesity, diabetes,
hypertension, and/or other metabolic related disorders.
BACKGROUND OF THE INVENTION
[0004] Obesity and other metabolic related disorders affect
millions of patients, and the number of patients suffering from
such disorders has increased in recent years. Morbid obesity is
often considered a serious and potentially life threatening
disorder, as it may lead to diabetes, hypertension and other
serious medical conditions. Since all of these disorders are
typically related to the digestive processes, treatment methods
often involve interrupting the normal digestive process to reduce
the absorption of food particles passing from the stomach through
the gastrointestinal system. Studies have also shown that reducing
intestinal contact with gastric chyme, which may influence the
secretion of certain hormones such as ghrelin which may stimulate
hunger, may also be a viable treatment for obesity and its
associated medical conditions. Although bariatric surgical
procedures, such as the Roux-en-Y gastric bypass and gastric sleeve
resection, have proven beneficial, these procedures are highly
invasive and typically involve removal of portions of the stomach,
stapling or suturing, which generally result in permanent
irreversible changes to the patient's digestive tract and carry a
substantial risk of surgical complications or death.
[0005] [0005 Although more recently, endoscopic procedures have
been developed to deliver less invasive therapies, such as the
gastric bypass sleeve, into the a patient's gastrointestinal
system, anchoring of such devices has proven difficult as the
stomach and gastrointestinal tract is fairly flexible and may
contort significantly during digestion. Additionally, the harsh
digestive environment within the stomach can tend to break down
foreign objects, such as an anchoring device, when placed in the
stomach for any length of time. The unique anatomy of the stomach
also presents challenges in anchoring a treatment device as devices
large enough to resist passage from the stomach through the
gastrointestinal tract may block the passage of nutrients and food
particles through the digestive system, while devices small enough
to allow passage of food and nutrients are often passed through the
digestive system. Due to these difficulties in anchoring treatment
devices in the stomach, many procedures still rely on invasive
techniques, such as suturing or penetrating tissues.
[0006] In light of the above, it would be beneficial to provide
improved devices, systems and methods for anchoring treatment
devices, and in particular anchoring of treatment devices in a
stomach of a patient for use in treatment of obesity and other
metabolic related disorders. It would be desirable to provide a
device and method for anchoring a treatment device in a
gastrointestinal tract or stomach of a patient that does not
require suturing, stapling, or resection of tissue, while allowing
the passage of nutrients and food particles through the digestive
system. It would also be beneficial to provide systems and methods
of treatment that allow for treatment of metabolic disorders by
limiting intestinal contact with stomach chyme and stomach
secretions therby influencing secretion of certain hormones, both
of which contribute to metabolic disorders including diabetes and
obesity. It is further desirable that such devices and methods are
robust enough to withstand the harsh environment of the stomach
while providing adequate anchoring in the unique morphology of the
stomach.
BRIEF SUMMARY OF THE INVENTION
[0007] The present invention generally provides improved medical
devices, systems and methods of treatment. Exemplary embodiments of
these devices and techniques can be used to anchor a treatment
device in a stomach of a patient, which is particularly useful in
treating metabolic disorders such as obesity (and related
disorders), diabetes, hypertensions, and the like. Such disorders
may be treated by anchoring a sleeve placed in the gastrointestinal
tract in the stomach so that the sleeve can reduce intestinal
contact with and absorption of gastric chyme or stomach secretions,
flowing from the stomach through the gastrointestinal tract.
[0008] Advantageously, the present invention allows for anchoring
of a treatment device, such as a bypass sleeve, in the stomach of a
patient by engaging a wall of the stomach and/or the
gastrointestinal tract at multiple locations, without the need for
stapling, suturing, resection, or other invasive modification of
the gastrointestinal system.
[0009] In an exemplary embodiment, the invention comprises an
anchor having an elongate element extending between a proximal end
and a distal end and further having aproximal and distal atraumatic
feature disposed at each end, wherein the anchor is attached to or
supports a treatment or diagnostic device. Each of the proximal and
distal atraumatic features are configured to inhibit tissue trauma
when urged against a tissue of the stomach or the gastrointestinal
tract, while the elongate element is sufficiently rigid an as to
resist bending between the proximal and distal ends and is
sufficiently long to inhibit advancement of the anchor around a
bend of a proximal intestine, such as the proximal portion of the
duodenum, when under anchoring loads.
[0010] In one embodiment, the treatment device comprises an
intestinal bypass sleeve having a lumen extending between a
proximal opening and a distal opening, wherein the sleeve comprises
a material substantially impenetrable to a flow of ingested matter,
such as ingested nutrients and food particles, the flow being in
contact with the walls of the stomach before passing into the
lumen. The proximal opening of the lumen is supported by the anchor
distally of the proximal end of the anchor so as to direct the flow
of ingested matter from the stomach into the lumen thereby reducing
contact of the ingested matter with the walls of the
gastrointestinal tract. In an embodiment particularly useful in
treating diabetes, the sleeve may prevent ingested matter from
contacting a portion of the duodenum, thereby influencing
production of certain hormones that affect diabetes, such as
ghrelin, a hormone that stimulates hunger.
[0011] In many embodiments, the distal atraumatic feature is sized
and configured to be advanced through a pyloric valve such that
when implanted the distal feature is disposed distal of the pyloric
valve and the proximal feature is disposed within the stomach. In
other embodiments, the distal atraumatic feature may be disposed in
a distal portion of the stomach and the proximal feature may also
disposed in the stomach albeit proximal of the distal feature.
Typically, in embodiments where the treatment device includes a
sleeve, the elongate element between the features at each end has a
profile smaller than the sleeve, and optionally, the distal feature
may radially support the proximal opening of the sleeve so that a
majority of a flow of ingested food advancing around the anchor
passes into the opening of the sleeve. In other embodiments, the
anchor is attached to the treatment device, often a sleeve, by a
tether or other such coupling structure and the proximal opening of
the sleeve may be supported by a separate structure, such as a
sliding seal, which supports the proximal opening of the seal,
typically by exerting an outward radially force so as to seal the
proximal end of the sleeve against a wall of the gastrointestinal
tract or the stomach. Such seals and support members may include
expandable rings or other expandable structures. Preferably, the
seal is slidable so as to allow atraumatic movement within the
gastrointestinal tract or the stomach.
[0012] In many embodiments, one or both of the atraumatic features
include expandable members having a collapsed configuration
suitable for delivery through the stomach, such as in an endoscopic
procedure, and an expanded configuration, so as to distribute
anchoring loads to inhibit tissue damage by an end of the elongate
element or member and may also prevent passage of the distal
feature across the pyloric valve or to help maintain a position of
the anchor. The expandable members may include balloons, rigid, or
non-rigid members, expandable wire loop structures, sinusoidal-type
structures, or any structures that may expand when released front a
collapsed configuration, may be expanded by inflation, or by
movement of a drawstring or other expanding mechanism.
[0013] In many embodiments, the elongate element is sufficiently
long to prevent end-to-end rotation in the stomach so as to
maintain a relatively stable position in the stomach for anchoring
the treatment or diagnostic device. Typically, the elongate element
is at least 10 cm in length. In a preferred embodiment, when the
distal atraumatic feature is disposed in a proximal portion of the
duodenum a proximal portion of the anchor engages a distal portion
of the stomach wall such that engagement of a proximal and distal
portion of the anchor with the tissues of the stomach or
gastrointestinal tract prevent the anchor from passing from the
stomach through the duodenum. In some embodiments, the length of
the elongate element and the distal and proximal features are
configured such that displacement of a longitudinal axis of the
anchor is limited by the engagement of the proximal and distal
portions of the anchor with tissues of the stomach and the
gastrointestinal tract so as to substantially maintain a position
of the anchor and to maintain a position of the sleeve, and/or the
distal feature, thereby maintaining the position of the anchor as
well as the flow of ingested matter from the stomach through the
sleeve.
[0014] Also disclosed are method for treating a patient having an
obesity or diabetes related disorder using the claimed anchor
implant. An exemplary method includes deploying an implant within a
gastrointestinal tract of the patient so that a proximal end of an
anchor of the implant is disposed in the stomach, wherein the
anchor comprises an elongate element having a proximal end and a
distal end, and an atraumatic feature disposed near each end;
supporting a therapeutic device, such as a sleeve, with the anchor
so that the sleeve extends along an intestine of the patient, and
so that ingested matter enters a lumen of the sleeve from the
stomach, the ingested matter being in contact with a wall of the
stomach; inhibiting advance of the anchor around a bend of the
intestine by engaging a proximal portion of the anchor against a
distal surface area of the stomach and by engaging a distal portion
for he anchor against a proximal surface area of the intestine and
by resisting bending of the elongate element between the proximal
and distal ends; and advancing a flow of the ingested matter, such
as ingested nutrients and particles of food, along the intestine
within the lumen of the sleeve.
[0015] These and other embodiments are described in further detail
in the following description related to the appended drawing
figures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1A is a view of a sectioned stomach and small bowel
with an intragastric anchor implant, in accordance with many
embodiments;
[0017] FIG. 1B is a view of a sectioned stomach and small bowel
with an inflatable embodiment of an intragastric anchor implant and
detachable fill-tube, in accordance with many embodiments;
[0018] FIG. 1C is a view of an intragastric anchor implant with a
rigid element conforming to an acutely-angled toroidal balloon, in
accordance with many embodiments;
[0019] FIG. 1D is a view of an intragastric anchor implant with a
rigid element conforming to an obtusely-angled toroidal balloon, in
accordance with many embodiments;
[0020] FIG. 1E depicts multi-chamber balloon configurations for
intragastric anchor implants, in accordance with many
embodiments;
[0021] FIG. 2 is a view of a sectioned stomach and small bowel with
intragastric anchor implant with a flexible section between
proximal and distal atraumatic features or tips, in accordance with
many embodiments;
[0022] FIG. 3A is a view of a sectioned stomach and small bowel
with an intragastric anchor implant supporting a sleeve with an
antral opening via a flexible connector, in accordance with many
embodiments;
[0023] FIG. 3B is a view of a sectioned stomach and small bowel
with an intragastric anchor implant supporting a sleeve with a
duodenal opening via a flexible connector, in accordance with many
embodiments;
[0024] FIG. 3C depicts sliding seal embodiments for sleeves, in
accordance with many embodiments;
[0025] FIG. 3D depicts a sliding seal for sleeves with a composite
structure, in accordance with many embodiments;
[0026] FIG. 4 is a view of a sectioned stomach and small bowel with
an inflatable embodiment of an intragastric anchor implant, in
accordance with many embodiments;
[0027] FIG. 5 is a view of a sectioned stomach and small bowel with
an intragastric anchor implant with a rigid element passing through
the pylorus, in accordance with many embodiments;
[0028] FIG. 6 is a view of a sectioned stomach and small bowel with
an intragastric anchor implant with an antral sliding seal, in
accordance with many embodiments;
[0029] FIG. 7 is a view of a sectioned stomach and small bowel with
an intragastric anchor implant with a duodenal sliding seal, in
accordance with many embodiments;
[0030] FIG. 8 is a view of a sectioned stomach and small bowel with
an intragastric anchor implant with an atraumatic feature including
loops, in accordance with many embodiments;
[0031] FIG. 9A is a view of a sectioned stomach and small bowel
with an intragastric anchor implant with a sliding seal including
leaflets, in accordance with many embodiments;
[0032] FIG. 9B is a view of an intragastric anchor implant with a
sliding seal including leaflets, in accordance with many
embodiments;
[0033] FIG. 10A is a view of a sectioned stomach and small bowel
with a one-piece intragastric anchor implant, in accordance with
many embodiments;
[0034] FIG. 10B is a view of a one-piece intragastric anchor
implant, in accordance with many embodiments;
[0035] FIG. 10C is a view of a one-piece intragastric anchor
implant with attachment tabs, in accordance with many
embodiments;
[0036] FIG. 11A is a proximal view of an intragastric anchor
implant with struts angling in opposite directions, in accordance
with many embodiments;
[0037] FIG. 11B is a distal view of an intragastric anchor implant
with struts angling in opposite directions, in accordance with many
embodiments;
[0038] FIG. 12 is a view of a sectioned stomach and small bowel
with an intragastric anchor implant with a single-piece atraumatic
feature-expandable sleeve support, in accordance with many
embodiments;
[0039] FIG. 13 is a view of a sectioned stomach and small bowel
with an intragastric anchor implant with a flexibly-attached sleeve
support, in accordance with many embodiments;
[0040] FIG. 14A is a view of a sectioned stomach with a parallel
endoscopic delivery system for an intragastric anchor implant, in
accordance with many embodiments;
[0041] FIG. 14B is a view of a sectioned stomach with a parallel
endoscopic delivery system for an intragastric anchor implant
extending a sleeve, in accordance with many embodiments;.
[0042] FIG. 14C is a view of a sectioned stomach with a parallel
endoscopic delivery system for an intragastric anchor implant
deploying an expandable sleeve support, in accordance with many
embodiments;
[0043] FIG. 15A is a view of a sectioned distal stomach with an
endoscope and overtube, in accordance with many embodiments;
[0044] FIG. 15B is a view of a sectioned distal stomach and
intestine with an endoscope and overtube with inflated balloon, in
accordance with many embodiments;
[0045] FIG. 15C is a view of a sectioned stomach and intestine with
an intragastric anchor implant being delivered distally through an
endoscope overtube, in accordance with many embodiments;
[0046] FIG. 15D is a view of a sectioned stomach and intestine with
an intragastric anchor implant being delivered distally through an
endoscope overtube, in accordance with many embodiments;
[0047] FIG. 16A is a view of a sectioned stomach and intestine with
an over the wire intragastric anchor implant delivery system, in
accordance with many embodiments;
[0048] FIG. 16B is a view of a sectioned stomach and intestine with
an intragastric anchor implant delivery system with a split
introducer, in accordance with many embodiments;
[0049] FIG. 16C is a view of a sectioned stomach and intestine with
an intragastric anchor implant delivery system with a split
introducer releasing a sleeve and expandable sleeve support, in
accordance with many embodiments;
[0050] FIG. 17A is a view of a sectioned stomach and intestine with
an intragastric anchor implant delivery system supporting a sensor,
in accordance with many embodiments;
[0051] FIG. 17B is a view of an intragastric anchor
implant-supported sensor with a sliding apposition structure, in
accordance with many embodiments.
DETAILED DESCRIPTION OF THE INVENT ION
[0052] The present invention generally provides improved medical
devices, system and methods for treatment of patients. As described
herein, the term "proximal" means nearest the point of origin,
within the context of the flow of food particles through the
digestive system, and "distal" means situated farthest from the
point of origin. For example, in reference to the stomach, a
"proximal" portion of the stomach refers to the portion nearest the
esophagus where the flow of food into the stomach originates,
whereas the "distal" portion of the stomach refers to the portion
nearest the pyloric valve where the flow of food particles leaves
the stomach. Similarly, the "proximal" portion of the duodenum
refers to the portion nearest the pyloric valve, from which the
flow of food particles entering the duodenum originates.
[0053] Exemplary embodiments of the present invention can be used
to anchor a treatment device in a stomach of a patient in treating
metabolic related disorders such as diabetes, hypertension, and
obesity (along with related disorders). Such treatments typically
include anchoring a sleeve placed in the gastrointestinal tract in
the stomach, such that the sleeve reduces the absorption of
ingested matter flowing from the stomach through the
gastrointestinal tract. Advantageously, the present invention allow
for anchoring of a treatment device, such as a sleeve, in the
stomach of a patient while still allowing sufficient flow of food
and nutrients through the gastrointestinal tract via the sleeve
without requiring stapling, suturing, resection, or other such
invasive modification of the gastrointestinal tissues. The
invention described herein exploits the geometry of the gastric and
intestinal anatomy to maintain an intragastric implant in a
relatively fixed position within the gastrointestinal tract without
attachment to the gastric watt. Specifically, the present invention
is directed to a gastric implant that comprises an intragastric
anchor and a therapeutic or diagnostic device coupled to the
anchor. The intragastric anchor of the invention limits the
movements of a device attached to it to the displacement available
to the anchor within the stomach and/or the duodenum.
[0054] In one embodiment of the invention, the intragastric anchor
has an elongate shape extending along the long axis of the stomach
from the antrum to the fundus such that displacement of the anchor
along the long axis due to gastric contractility or other causes is
limited by the gastric anatomy of the fundus and pylorus.
Similarly, the elongate anchor is configured to be longer than the
transverse width of the stomach and thus too long to be flipped end
over end within the stomach by gastric contractility. Thus, the
intragastric anchor provides a relatively stable platform on which
to anchor bariatric or other therapeutic or diagnostic devices.
Once deployed within the stomach, the anchor is configured to be
larger than the pyloric valve to prevent its passing out of the
stomach and into the small bowel. This configuration enables the
intragastric anchor to maintain a relatively fixed position and
orientation within the gastrointestinal tract. The present
invention is further directed to a method for anchoring a
therapeutic device or a diagnostic device within the stomach in a
relatively fixed position, that is with a relatively stable
position and orientation, while being free from attachment to the
stomach wall, the method comprising positioning an anchor according
to the invention in the stomach of a patient between the fundus and
the pyloric valve and coupling a therapeutic device or a diagnostic
device to the anchor.
[0055] In another embodiment, the intragastric anchor has an
elongate shape extending from the antrum through the pylorus to the
duodenum such that displacement of the anchor along the long axis
due to gastric or intestinal motility or other causes is limited by
the anatomy of pylorus and proximal duodenum. Similarly, the
elongate anchor is configured to be longer than can be accommodated
by the relatively fixed curvature of the proximal duodenum. Thus
configured a transpyloric intragastric anchor is too long to be
fully passed out of the stomach and into the small bowel and may
serve as a relatively stable platform on which to anchor bariatric
or other therapeutic or diagnostic devices within the
gastrointestinal tract. Once deployed across the pylorus, a narrow
portion of the anchor is configured small enough, typically 5 mm or
smaller, to allow food particles and nutrients to pass around the
anchor through the pylorus and into the duodenum. This
configuration enables the transpyloric intragastric anchor to
maintain a relatively fixed position and orientation within the
gastrointestinal tract without compromising the flow of nutrients
out of the stomach. The present invention is further directed to a
method for anchoring a therapeutic device or a diagnostic device
within the stomach in a relatively fixed position, that is with a
relatively stable position and orientation, while being free from
attachment to the stomach wall, the method comprising positioning
an anchor according to the invention across the pylorus of a
patient between the antrum and the duodenum; and coupling a
therapeutic device or a diagnostic device to the anchor.
[0056] Having secured the anchoring implant within the
gastrointestinal tract, any number of devices may be attached to
it. In one embodiment, the device is a therapeutic device. For
example, a bypass sleeve may be secured to extend from the
esophagus to the jejunum, supported by a relatively fixed
intragastric anchor. Having secured the anchoring implant within
the gastrointestinal tract, any number of devices may be attached
to it. In one embodiment, the device is a therapeutic device. For
example, a bypass sleeve may be secured to extend from the body of
the stomach to the jejunum, supported by a geometrically-fixed
intragastric anchor. Similarly, a duodenal-jejunal bypass sleeve
extending from the duodenal bulb into the jejunum may be supported
by such an anchor. Also similarly, devices restricting gastric
inflow and/or outflow may be supported by an intragastric
anchor.
[0057] Similarly, diagnostic devices, such as for example a pH
sensor, may be supported within the gastrointestinal tract by an
intragastric anchor. By way of example, when configured to maintain
a pH sensor within the duodenum, an intragastric anchor may include
a duodenal extension, extending from the body of the anchor through
the first bend of the duodenum and to the ampulla of Vater to
support the sensor in a relatively fixed position within the
intestine. To minimize the risk of ductal blockage the sensor is
preferably allowed some degree of !notion within the small bowel.
Furthermore, since the intragastric anchor will move in a
restricted fashion in response to normal gastric and intestinal
motility and likewise move the pH sensor affixed to it, the pH
sensor may be slidably coupled to the intestine by an atraumatic
sliding apposition structure. Regular sliding along the intestinal
wall reduces the possibility of hyperplastic tissue ingrowth,
minimizes pressure on healthy mucosa, minimizes the likelihood of
duct blockage, and enhances the removability of the sensor. The
combination of elongate intragastric anchor and sliding apposition
structure improves upon stenting, stapling, suturing, and other
fixation methods for implanted diagnostic devices by avoiding the
tendency of such implants to migrate or to become unremovable
through tissue ingrowth and scarring.
[0058] In a preferred embodiment, the intragastric anchor revolves
around bariatric therapy. A specific implementation described in
this disclosure mimics the mechanisms by which Roux-en-Y gastric
bypass surgery is thought to operate while advantageously avoiding
the severe, invasive, and permanent surgical changes to the
patient's anatomy associated with such procedures. An anchored
bypass sleeve isolates a section of the small bowel from gastric
chyme and secretions, delays exposure to digestive enzymes by
bypassing the ampulla of Vater, and reduces nutrient absorption by
bypassing a section of the small bowel.
[0059] Configured to secure an anchored bypass sleeve within the
duodenum, the intragastric anchor may support the proximal opening
of the sleeve in the duodenal bulb or duodenum distal to the
pylorus, or in the antrum or body of the stomach proximal to the
pylorus such that it is prevented from migrating distally into the
small bowel. Since the intragastric anchor will move in a
restricted fashion during normal gastric motility and will likewise
move the bypass sleeve affixed to it, the proximal opening of the
anchored bypass sleeve is preferably slidably coupled to the
surrounding lumen by an atraumatic sliding seal. The combination of
elongate intragastric anchor and sliding seal improves upon
stenting, stapling, suturing, and other fixation methods by
avoiding the tendency of gastrointestinal tract implants to
migrate, cause perforations, or to become unremovable through
tissue ingrowth and scarring.
[0060] One embodiment of an anchored bypass sleeve device includes
a radially compliant proximal section of bypass sleeve extending
from the duodenum to an intragastric anchor implant in the stomach.
The radially compliant section of sleeve maintains outward radial
pressure on the pylorus and aids in guiding food particles to the
more distal portions of the sleeve. Radial compliance may be
inherent in the construction of the proximal sleeve or it may be
imparted by an expandable sleeve support such as a sinusoid or
strut structure. The distal section of the bypass sleeve extends
into the small bowel.
[0061] The anchored bypass sleeve is delivered to the target site
via a (prepositioned guidewire, in parallel with an endoscope,
through an overtube slid over an endoscope, or with a flexible
delivery enclosure. The device may include multiple radiopaque
markers along its length to aid deployment under fluoroscopic
guidance. For example, markers may be placed at the distal end of
the bypass sleeve, at the distal end of the anchor, at the proximal
end of the anchor, and at the sliding seal. Portions of the anchor
such as the rigid element may be configured for relative
radiopacity.
[0062] In a first specific aspect of the present invention, an
intragastric anchor implant comprises an elongate anchor adapted to
extend substantially from the fundus to the pyloric valve in a
patient and a therapeutic or diagnostic device, such as a bariatric
sleeve, coupled to the anchor. The elongate anchor will usually be
adapted to remain positioned in the stomach without the need for
suturing, stapling, or other forms of attachment. The length and
geometry of the anchor will typically be selected to assure that
the anchor remains within the stomach without being ejected through
the pyloric valve or otherwise adversely affecting the patient. The
therapeutic or diagnostic device will be either fixedly or movably
coupled to the anchor, and may be coupled at one or more points. In
the case of a bariatric sleeve, the bariatric sleeve will be
configured to act in a manner similar or analogous to the Roux-en-Y
gastric bypass, typically having a central passage with an upper or
proximal opening positionable in the esophagus and a lower or
distal outlet positionable in the intestines, or in some instances
within the stomach. The bariatric sleeve may have a variety of
particular configurations: it may be either rigid, flexible, or
have portions of each; it may be either straight, curved, or have
other combination geometries; and/or it may comprise nestable or
hinged links in order to have a shape-lock configuration which
facilitates introduction and subsequent reconfiguration within the
stomach. The elongate anchor will usually have upper and lower
atraumatic ends or features, where the atraumatic end may be a
bulbous geometry, a looped structure, or the like.
[0063] The bariatric sleeve will usually have a resilient sliding
seal at its proximal end, which is adapted to slide against or
slidably engage the inner wall of the esophagus. The sliding seal
may be an inflatable balloon or cuff structure, or it may be a
resilient flared structure, or it may be a stented structure to
provide a resilient opening force, or the like. Usually, the
bariatric sleeve will also slidably extend through the pyloric
valve so that both the upper and lower ends of the sleeves may move
within the gastroesophageal junction and pyloric valve as the
stomach changes positions.
[0064] In another aspect of the present invention, a method for
treating obesity comprises positioning an anchor across the pylorus
of a patient. The anchor will typically be positioned between the
antrum and the duodenal bulb and will usually be free from
attachment to the intestinal or stomach wall. A bypass sleeve is
coupled to the anchor, and the anchor positions a proximal opening
of the sleeve in the antrum, duodenal bulb, or duodenum and a
distal outlet of the sleeve in the small bowel. The proximal
opening of the sleeve is preferably slidably disposed against a
lunienal wall to guide food particles into the sleeve and inhibit
food bypass.
[0065] FIG. 1A describes an intragastric anchor implant 100
supporting an intestinal bypass sleeve 101 that is substantially
impenetrable to nutrients and food particles, in accordance with
many embodiments. The sleeve is configured to line the intestine
such that nutrients and food particles pass through the sleeve
lumen and are prevented from contacting the intestinal wall while
passing inside the sleeve. A preferred embodiment of the sleeve is
configured to line the duodenum and proximal jejunum at least to
the ligament of Treitz. Alternate embodiments may include shorter
or longer bypass sleeves. An embodiment of the intragastric anchor
implant includes proximal and distal atraumatic tips or features,
103 and 104 respectively, connected by a substantially rigid
element 102. In an embodiment in which atraumatic features 103 and
104 are balloons, rigid element 102 may serve as a conduit to
distribute pressurized fluid between the balloons as well as acting
as preventing the anchor's passage out of the stomach in the event
of accidental balloon deflation. A preferred embodiment of the
rigid element is at least 10 cm long such that it will be unable to
pass through the tight and relatively fixed turns of the proximal
duodenum, although alternate embodiments may employ rigid elements
that are shorter and longer than 10 cm. Some embodiments of the
rigid element may be configured for substantial radiopacity such
that the position of the rigid element within an anatomical lumen
may be confirmed fluoroscopically. These embodiments may include
barium, tantalum, gold, metallic particles, or any suitable
radio-opaque material in their construction.
[0066] The embodiment of the intragastric anchor implant depicted
in FIG. 1A is configured to geometrically limit movement of the
distal atraumatic feature and sleeve opening relative to the
pylorus by extending substantially between the antrum and fundus of
the stomach. Although this embodiment includes a toroidal distal
atraumatic feature 104 which supports and holds open the proximal
sleeve opening 106, alternate embodiments may include U-shaped
distal features, multiple balloons, or any other suitable form
which includes a space which holds open the proximal end of an
intestinal bypass sleeve and be connects it to the anchor implant
100. The distal atraumatic feature is configured to be engaged by
peristaltic action of the antrum such that it is pulled towards the
pylorus while being sufficiently large, approximately 25 mm in
diameter although larger and smaller configurations are possible,
not to pass through the pylorus. A proximal portion 105 of the
intestinal bypass sleeve 101 is configured to slidably engage the
gastrointestinal tract such as one or more of the pylorus, bulb of
the duodenum, duodenum, and jejunum. The proximal portion of the
intestinal bypass sleeve may be configured to retain sufficient
compressive strength to slide back and forth through the pyloric
valve as gastric peristalsis displaces the intragastric anchor
implant within the stomach.
[0067] A preferable embodiment of a sleeve would include a portion
that is capable of smoothly changing diameter to accommodate
stomach and small bowel peristalsis as well as the opening and
closing of the pyloric sphincter forming a seal such that food
particles exit the stomach through the proximal opening 106 of the
intestinal bypass sleeve 101. To achieve such compressive strength
and the ability to change diameters a portion of the sleeve as
shown in FIG. 3D may be constructed of a braided material embedded
in an elastomer such as silicone, polyurethane, thermoplastic
elastomer such as Santoprene, or any suitably compliant material.
The braided material may be polypropylene monofilament, stainless
steel, nickel-titanium alloy, fluoropolymer, or any suitable braid
material. More preferably a braid-reinforced proximal portion of
the sleeve may be configured to provide sufficient radial
compliance to expand when the pyloric sphincter relaxes while
exerting minimal surface pressure on the sphincter when it is
closed. A bypass sleeve thus constructed will also offer
significantly improved resistance to twisting and kinking along its
length within the small bowel, preventing possible blockages.
[0068] The embodiment of an intragastric anchor implant depicted in
FIG. 1 includes a toroidal distal atraumatic feature 104 angled
with respect to the main axis of the anchor towards the pylorus
such that the bypass sleeve exits the atraumatic feature more
directly in the direction of the pylorus. Another embodiment of an
intragastric anchor implant may include a distal atraumatic feature
rotated 90 degrees such that its central axis is orthogonal to the
main axis of the intragastric implant.
[0069] FIG. 1B depicts an embodiment of an intragastric anchor
implant supporting an intestinal bypass sleeve attached
circumferentially to a substantially rigid element 102 which
includes a lumen 108 to which bypass sleeve 101 is connected and
through which chyme (partially-digested food particles) may pass. A
rigid element 102 included in any embodiment of an intragastric
anchor implant may include a one-way valve and port 106 through
which air, carbon dioxide, saline; or another suitable fluid may be
introduced via a fill tube 107 into proximal and distal atraumatic
features 103 and 104 when configured as balloons.
[0070] FIG. 1C depicts an embodiment of an intragastric anchor
implant supporting an intestinal bypass sleeve 101 attached to the
central opening 111 of a toroidal distal feature balloon 104 which
is itself attached to a flattened, spoon-shaped section 109 of
rigid element 102. The sleeve 101, balloon 104, and rigid element
102 may be attached with UV curing glue, silicone glue, RF welding,
or any other suitable technique. The flattened-section 109 may
extend proximally to make room for food particles to reach the
mouth of the bypass sleeve 101. The rigid element may include a
lumen 110 to serve as a conduit distributing pressure between the
balloons. The sleeve opening supported by the distal balloon may be
angled acutely relative to the main axis of the intragastric anchor
implant,
[0071] FIG. 1D depicts an embodiment of an intragastric anchor
implant supporting an intestinal bypass sleeve 101. The sleeve
opening 120 supported by the distal balloon may be angled obtusely
relative to the main axis of the intragastric anchor implant to
separate the sleeve opening 120 from the rigid member and improve
exposure of the sleeve opening to gastric peristalsis carrying food
particles.
[0072] FIG. 1E depicts various examples of embodiments of both the
proximal 115 and distal 116 balloons configured to be manufactured
by RF welding or similar techniques starting from a flat pattern
119 of multiple layers of material such as polyurethane
thermoplastic. Chambers 118 in a distal balloon may be arranged
around an intestinal bypass sleeve opening 117 such that they
support it when inflated. Such balloons may be attached to a rigid
element 102 via UV curing glue; heat-staking, or any other suitable
attachment method,
[0073] FIG. 2 depicts an embodiment of an intragastric anchor
implant 200 with a flexible section 205 connecting distal and
proximal atraumatic feature balloons, 204 and 203 respectively,
supporting a therapeutic device, such as an intestinal bypass
sleeve 201 as shown in this embodiment. The flexible section 205
may be constructed of flexible material such as elastomer, polymer,
or fiber, or may be constructed with a hinge or plurality of hinged
or liked joints. This flexible configuration allows the distal
balloon 204 of an intragastric anchor implant 200 to rotate to face
the pylorus, accommodating the curvature of the stomach, while the
entire structure retains sufficient stiffness to limit the movement
of the distal balloon and sleeve opening relative to the pylorus.
The distal balloon 204 may include a smooth outer surface or it may
be ridged and include several sub-chambers. A preferred embodiment
of an intragastric anchor implant may include a fill-valve 206
connector for a detachable fill tube mounted on the proximal
balloon. Flexible connecting tubes 207 and 208 may connect the
fill-valve to rigid element 202 and distal atraumatic feature
204.
[0074] FIG. 3A depicts an embodiment of an intragastric anchor
implant 300 supporting an intestinal bypass sleeve 301 via a
flexible connector 305. The flexible connector may connect the
proximal end, outer surface, or inner surface of the bypass sleeve
301 to a rigid element 302 or to distal atraumatic feature 304. In
a preferred embodiment the connector connects the rigid element 302
to the inner surface of the bypass sleeve at a point distal to the
sleeve's seal 306 via a coupling structure 308 such that the sleeve
proximal opening is free to expand with sliding contact against the
surrounding stomach, pylorus, or intestinal wall. In the embodiment
depicted in FIG. 3A, the length of the flexible connector 305 and
distance from the sleeve connection point are sized to maintain the
sleeve opening in a variable but relatively constant position
within the antrum portion of the stomach. In alternate embodiments,
the connector length and connection point may be sized to maintain
the position of a slidably-coupled sleeve opening within the
pylorus, duodenal bulb, duodenum, or any advantageous position
within the gastrointestinal tract. In the embodiment depicted in
FIG. 3A, the proximal opening 306 of the bypass sleeve 301 is
configured to slidably couple to the mucosal surface of the antrum
such that substantial contact is maintained as the intragastric
anchor implant is displaced within the stomach by gastric and
intestinal motility. The friction of sliding contact may be reduced
by coating a portion of the external surface of the bypass sleeve
301 with a hydrophilic polymer, parylene, or other suitable
friction-reducing coating. In the embodiment depicted in FIG. 3A,
the proximal opening of the bypass sleeve 301 is configured with a
radiused edge 307 such that the sleeve presents an atraumatic
surface compatible with sliding contact. Alternate embodiments may
position a slidable coupled proximal sleeve opening within the
duodenal bulb, duodenum, or any advantageous position within the
gastrointestinal tract.
[0075] FIG. 3B depicts an embodiment of an intragastric anchor
implant supporting an intestinal bypass sleeve with a flexible
connector 305. The connector may be constructed of a polymeric
elastomer, fiber reinforced elastomer, polymer monofilament, or any
suitable material. In this embodiment, a proximal portion 310 of
the sleeve 301 is configured to be slidably coupled to the inner
surface of the duodenum and the connector 305 attaches to the
sleeve's proximal opening with a coupling element 311 leaving the
opening substantially patent such that the passage of nutrients and
food particles is substantially unimpeded. The coupling element may
be an integrally molded part of connector 305 or may be constructed
of nickel-titanium alloy or stainless steel wire struts, or any
suitable material of sufficient strength to resist forces imparted
by peristalsis while being sufficiently compressible to allow the
bypass tube and anchor assembly to be delivered in a small diameter
package.
[0076] FIG. 3C depicts embodiments of a slidably coupled bypass
sleeve 342 configured for atraumatic sliding upon the surface of an
anatomical lumen while accommodating varying lumen diameters and
shapes. In these embodiments, a sliding seal section of the
intestinal bypass sleeve 342 is configured for substantial
apposition against and atraumatic sliding upon the surface of
anatomical lumen 348. In order for the opening of a bypass sleeve
to conform to the internal topography of a section of the
gastrointestinal tract, it may be configured to have a mechanical
compliance similar to or less than that of the lumenal wall against
which it will slide while at the same time generating enough
outward radial pressure to maintain substantial apposition against
that wall. This may be achieved with a stent-like structure, such
as compressible ring 340, incorporated into the proximal sleeve
which may also include a radiused proximal edge 341. The
compressible ring 340 may include at least one sinusoidal element
to allow compression and expansion such that outward radial
pressure may be applied to an anatomical lumen so as to create a
sliding seal when combined with a flexible circumferential tube 347
made of material such as polypropylene, fluoropolymer film or the
like. The ring may be made of polymer such as polypropylene or
fluoropolymer, nickel-titanium alloy, stainless steel, or any
suitable material. An alternate embodiment of a sliding seal
section of a bypass sleeve includes a radiused low durometer
elastomeric cuff 345 attached to a bypass sleeve opening 346.
Another alternate embodiment includes a tapered low durometer
elastomeric wiper 343 attached to the proximal sleeve opening 344,
or any suitable structure that provides appropriate compliance and
sleeve apposition.
[0077] A preferred embodiment of a sliding seal, as shown in FIG.
3C, employs overlapping leaflets 331 attached to a coupling ring
330 which provides circumferential mechanical support and which may
attach to intestinal bypass sleeve 332. The leaflets, while fixed
to coupling ring 330 at their bases, may slide past one another
along the rest of their lengths to increase or decrease the
effective diameter of the sealing surface. The leaflets may be
configured with outward curvature such that effective diameter D is
larger than the diameter of the coupling ring and may interfere
somewhat with an anatomical lumen to provide a slideably coupled
seal. The leaflets may be made of flexible material such as
thermoplastic elastomer, silicone, fluoropolymer, polypropylene, or
any suitable material.
[0078] A preferred embodiment of a sliding seal section of
intestinal bypass sleeve 320, which typically includes a proximal
opening of the intestinal bypass sleeve, incorporates a compliant
composite structure as shown in FIG. 3D and in FIG. 5 (in sectioned
and partially-sectioned cutaway views, respectively) in which a
fibers in a tubular braid 321 are embedded in an elastomeric matrix
such as silicone rubber, polyurethane, thermoplastic elastomer such
as Santoprene, or any suitable elastomeric matrix material. Such a
structure enables a bypass sleeve of varying diameters to be
constructed such that a larger diameter may form a duodenal or
antral sliding surface while the entire structure may be contracted
into a smaller diameter for delivery into a target site within the
gastrointestinal tract, maintaining substantially smooth inner and
outer surfaces. Similarly, a smaller diameter section forming a
pyloric sliding surface 324 may be defined and set into the
elastomeric composite structure, limiting the reaction force
exerted on particular sections of the gastrointestinal tract.
Sliding surfaces defined by the smaller diameter section may
include pyloric and duodenal sliding surfaces. A relatively smaller
diameter section at the proximal opening of the bypass sleeve may
also be set into the elastomeric composite structure such that an
atraumatic radiused edge 322 of a sliding seal is formed. Such an
atraumatic leading edge may also be formed through molding,
heat-setting, or any suitable process. A bend 323 may also be set
into such an elastomeric composite structure such that the flexible
sleeve tends to settle into specific bends in the gastrointestinal
tract such as the first bend of the duodenum. Sliding surfaces
constructed in this manner may also include a coating of
hydrophilic polymer, parylene, or other suitable friction reducing
coating.
[0079] FIG. 4 depicts an embodiment of an inflatable intragastric
anchor implant 400 supporting via a flexible tether 403 an
intestinal bypass sleeve 401 having a proximal end (shown in
sectioned cutaway view) configured as a sliding seal 406 with a
curved opening edge 404 configured for sliding and positioned
within and slidably coupled to the duodenal bulb and duodenum. As
shown in FIG. 4, rigid element 402 may be attached to an outer
surface of inflatable portion 405, although the rigid element may
also be attached to an inner surface of inflatable portion or in an
intermediate position. The rigid element 402 and may include an
inflation port 407 with a one-way valve to retain pressure within
the implant. The rigid element is configured to be at approximately
10 cm long to prevent the intragastric anchor implant from exiting
the stomach should the inflatable portion 405 deflate, although
longer and shorter embodiments of the rigid element are possible.
Tether 403 may connect directly to the rigid element as shown in
FIG. 4, or alternately may connect to the inflatable portion.
[0080] FIG. 5 depicts an embodiment of an intragastric anchor
implant 500 configured to position a substantially rigid element
502, through the pyloric valve such that it straddles the antrum
and proximal duodenum and supports an intestinal bypass sleeve 501
that is substantially impenetrable to nutrients and food particles.
The sleeve 501 is configured to line the intestine such gastric
chyme passes through the sleeve lumen and is prevented from
contacting the intestinal wall while passing inside the sleeve. A
preferred embodiment of the sleeve is configured to line the
duodenum and proximal jejunum, such as a 40 cm to 80 cm portion of
the small bowel, at least to the ligament of Treitz. Alternate
embodiments may include shorter or longer intestinal bypass
sleeves. A preferred embodiment includes a rigid element 502 that
is at least 10 cm long such that it will be unable to pass through
the tight and relatively fixed turns of the proximal duodenum,
although alternate embodiments may employ rigid elements that are
shorter or longer. A preferred embodiment of the rigid element 502
is approximately 3 to 5 mm in diameter, although practicable
embodiments of larger and smaller diameters are possible depending
upon material selection. The rigid element 502 may be constructed
of acid-resistant materials such as polypropylene, fluoropolymer,
nickel-titanium alloy, stainless steel, or any suitable material.
Sonic embodiments of the rigid element 502 may be configured for
substantial radiopacity such that the position of the rigid element
within a biological lumen may be confirmed fluoroscopically. These
embodiments may include barium, tantalum, gold, metallic particles,
or any suitable radio-opaque material in their construction. Since
an intragastric anchor implant, although remaining in a relatively
stable position, will be subject to movement imparted by gastric
and intestinal motility it is advantageous for the rigid element
502 to have a substantially smooth and even surface such that it
may slide relatively unimpeded against pyloric tissue. Alternate
embodiments of the anchor may include a friction-reducing coating
such as a hydrophilic polymer, parylene, or the like, on the outer
surface of the rigid element 502 to reduce the possibility of
mucosal erosions in the pylorus and surrounding tissues. The rigid
element 502 is located between proximal and distal atraumatic
features, 503 and 504 respectively, which spread the mechanical
loads imparted by gastric motility over relatively large surface
areas.
[0081] Embodiments of these atraumatic features, 503 and 504, may
include pressurized fluid-filled balloons, or non-pressurized
hollow or solid compliant projections including ribs, fins, rods,
domes, bulbs, prismatic shapes, or other flexible features capable
of spreading mechanical loads through mechanical deflection over a
relatively large area. The compliant projections may be constructed
of acid-resistant low durometer elastomer such as silicone rubber,
polyurethane, Santoprene, and the like, or they may be constructed
of loops, arcs, braids, or networks of polymer such as
polypropylene or fluoropolymer or of springy metal such as
superelastic titanium alloy or stainless steel. Wire embodiments of
the atraumatic features may be encased in acid-resistant flexible
membrane such as silicone elastomer, thermoplastic elastomer such
as Santoprene, polyurethane, PTFE, and the like to protect tissue
or they may be exposed, particularly in the case of a distal
atraumatic feature 504 which may be contained within an intestinal
bypass sleeve 501. Alternately the proximal and distal atraumatic
features may be rigid as the proximal atraumatic feature 1003
depicted in FIG. 10B and configured to distribute mechanical loads
over relatively large surface areas without substantially
deforming. The proximal atraumatic feature resides in the stomach
and serves to shield gastric tissue from the rigid element's
proximal end. In the embodiment depicted in FIG. 5, the distal
atraumatic feature 504 resides in the duodenal bulb or proximal
duodenum and serves to connect the intragastric anchor implant to
the bypass sleeve as well as shielding the small intestine from the
distal end of the rigid element. The distal atraumatic feature may
be configured to substantially fill the duodenal bulb as shown in
FIG. 8 or to be suspended within the bypass tube's proximal
opening, contacting the bypass tube only at a few connection points
with fins 505 as shown in FIG. 5 or with struts 1006 as shown in
FIG. 10B, or any suitable connection element.
[0082] The embodiment of the intestinal bypass sleeve shown in the
partially-sectioned cutaway view in FIG. 5 is configured to
slidably couple with the duodenum. As shown in FIG. 5, this
coupling with the duodenal wall is achieved by a sliding seal 507
forming the proximal portion of the intestinal bypass sleeve 501
constructed with braid 506 embedded in silicone elastomer,
thermoplastic elastomer such as Santoprene, or other suitable
flexible matrix material set into a fully expanded state which is
slightly larger in diameter than the expected diameter of the
proximal duodenum or duodenal bulb. Compliance fins 505 may also
provide radial expansion force to aid in coupling sliding seal 508
to an anatomical lumen. In an embodiment of the invention including
a sliding seal made as a composite structure with braided fibers
embedded in an elastomeric matrix, a contact zone of larger
diameter than the majority of the intestinal bypass sleeve 501 and
a curved proximal opening edge 507 configured for sliding 110 may
be defined in manufacturing. This larger diameter contact zone
forms the sliding seal which maintains a constant gentle pressure
against the intestinal wall such that the contact zone conforms to
differences in diameter and shape as it slides back and forth
within the duodenum in response to gastric and intestinal
motility.
[0083] As shown in FIG. 5, a proximal section of an intestinal
bypass sleeve may be pre-formed into an curved or bent
configuration such that the proximal section of the sleeve will
tend to settle into the first bend of the duodenum. A preferred
embodiment includes a proximal portion of the bypass sleeve formed
of flexible mesh or braided material 506 embedded in an elastomeric
matrix such as silicone, polyurethane, thermoplastic elastomer such
as Santoprene, or the like. The braid serves to maintain smooth,
wrinkle-resistant bends and accommodates changes in diameter while
also helping to spread the thrust load produced by stomach
motility, such as peristalsis, acting upon the intragastric anchor
implant.
[0084] FIG. 6 depicts an embodiment of an intragastric anchor
implant 600 supporting an intestinal bypass sleeve 601 (shown in
partially-sectioned view) with a proximal opening configured as a
sliding seal 603 slidably coupled to the antrum and distal stomach.
The intragastric anchor implant may include a rigid element 602
which may be coupled to the bypass sleeve 601 by flexible internal
ribs 604 formed of elastomeric material such as Santoprene or
silicone, flexible polymer such as polypropylene or, fluoropolymer,
metal such as nickel-titanium alloy, or any suitable compliant
material. The elastomeric coupler serves as a distal atraumatic
feature 605 for the end of the rigid element such that forces
imparted by gastric and duodenal motility are broadly distributed
to the duodenum. A radially compliant connecting structure 606
connects sliding seal 603 to atraumatic feature 605, passing
through the pyloric valve with rigid element 602.
[0085] FIG. 6 further illustrates a mechanism by which this
embodiment of the anchor implant, as well as many of the other
embodiment described herein, substantially maintains its anchoring
position within the stomach. As shown in FIG. 6, a distal portion
of the anchor implant near the distal feature is engaged with the
tissue at the pyloric valve at Point A and a proximal portion of
the anchor, the proximal feature, is engaged with a distal portion
of the stomach wall at point B such that a longitudinal axis of the
anchor, the X-axis, is limited in its range of movement. By
engaging a tissue of the patient with a proximal portion and a
distal portion of the anchor, the movement of the anchor is limited
such that the anchor is prevented from rotating to an angle that
would allow the anchor to pass through the proximal duodenum.
Additionally, the length of the elongate element may be
sufficiently rigid to prevent bending or curvature that would allow
passage of the element through the proximal duodenum. Thus, by
engaging the tissues of the patient as described, the claimed
implant and elongate element allow for anchoring without the use of
invasive techniques such as suturing of tissues. Furthermore, as
the above mechanisms limit the displacement of the longitudinal
axis the anchor may be configured to maintain a desired angle or
axis within the stomach so as to achieve a desired flow of ingested
matter or optimal anchoring position for a given application.
[0086] FIG. 7 depicts an embodiment of an intragastric anchor
implant 700 supporting an intestinal bypass sleeve 701 with a
flexible connector 702 such that the opening of the sleeve 701
remains slidably coupled in relatively constant position within the
duodenum distal to the duodenal bulb. A flexible connector 702 may
be constructed of polymeric elastomer, a fiber reinforced
elastomer, a polymer monofilament, or any suitable material or
combination of materials. The flexible connector 702 may be
configured with sufficient rigidity to transmit compressive
mechanical loads as well as tensile loads or it may be configured
such that it transmits only tensile loads. A connector 702 may be
coupled to a bypass sleeve with a compliant coupling structure 703
allowing temporary compression to a smaller diameter for
deliverability and a substantially open lumen such that nutrients
and food particles may pass relatively unimpeded. The connector
coupling structure 703 may include an elastomeric polymer fin
structure, a superelastic nickel-titanium wire structure, or employ
any suitably flexible material. The coupling structure 703 may
support a sliding seal configured to slideably couple the proximal
opening of intestinal bypass sleeve 701 to an anatomical lumen The
distal atraumatic feature 705 covers the rigid element's distal end
providing relatively large, compliant surfaces within the duodenum
while retaining a relatively open structure such that nutrients and
food particles may pass through to the sleeve opening relatively
unimpeded. A proximal atraumatic feature 706 may be configured with
folded-over fins to present a larger compliant surface area to the
surrounding tissues. The atraumatic features or caps, 705 and 706,
may be made of any suitable elastomeric material or may include a
combination of materials such as silicone and superelastic
nickel-titanium, silicone and stainless steel, silicone and polymer
monofilament such as polypropylene, or any suitable compliant
material or combination of materials. Alternate embodiments may
include at least one fluid-pressurized balloon or non-pressurized
bulb as one or both of the atraumatic features.
[0087] FIG. 8 depicts an embodiment of an intragastric anchor
implant 800 supporting an intestinal bypass sleeve 801 (shown in
cutaway view) that is slidably coupled with the duodenum and
duodenal bulb via sliding seal 803. In this embodiment, the anchor
is coupled to the bypass sleeve 801 via slender loops 804, such as
wire loops, which serve as an atraumatic feature to distribute and
transfer mechanical loads from the anchor to the bypass sleeve and
duodenum while presenting a very small cross-sectional area and
little resistance to the passage of nutrients and food particles.
The slender loops 804 may also be configured to interfere with the
surrounding bypass sleeve 801 such that they provide radial
compliance to the sliding seal 803 to aid in maintaining apposition
of the proximal sleeve opening to the duodenal wall. Alternately
the slender loops may be configured to connect only to a portion of
the bypass sleeve 801 such as the proximal opening or a portion
distal to the opening, allowing the unconnected portions of the
loop structure free to move within the bypass sleeve 801. In a
preferred embodiment, the slender loops 804 are made of
superelastic nickel-titanium alloy whereas alternate embodiments
may employ stainless steel alloys, polymer monofilaments,
thermopolymer such as polypropylene, fluoropolymer, thermoplastic
elastomer such as Santoprene, or any suitable material.
[0088] FIGS. 9A and 9B depict an embodiment of an intragastric
anchor implant 900 supporting an intestinal bypass sleeve 901. The
implant includes a rigid element 902 configured to pass from the
antrum section of the stomach through the pyloric valve and into
the duodenal bulb. Proximal and distal atraumatic features, 903 and
904 respectively, serve to spread and transfer mechanical loads
preventing tissue erosion and reducing the likelihood of
perforation. A sliding seat 905 which slideably couples the
proximal opening of the intestinal bypass sleeve 901 to the
intestinal lumen may include a plurality of overlapping leaflets
906 configured to conform the sliding seal's diameter to the
intestinal lumen's diameter. The leaflets 906 and atraumatic
features may be made of a flexible thermoplastic elastomer such as
Santoprene, thermoplastic polymer such as polypropylene,
fluoropolymer, or any suitable material. Alternately, they may
include multiple materials such as polypropylene and Santoprene,
fluoropolymer and nickel-titanium alloy, or any suitable
combination of materials that results in appropriate compliance and
conformability. The distal atraumatic feature 904 may include a
coupling ring 907 configured to aid coupling of the intestinal
bypass sleeve 901 to the anchor implant assembly via thermal
bonding such as heats taking, insert molding, or other suitable
connection means. The coupling ring 907 may be coupled to the
distal atraumatic fixture 904 via fins 909 (as shown in FIG. 9B),
loops, struts, or other suitable connection elements. A preferred
embodiment of the intragastric anchor implant includes an
intestinal bypass sleeve 901 made of polypropylene film and a
distal feature 904 made of melt-bonding compatible material such as
polypropylene polymer or Santoprene thermoplastic polymer. Some
embodiments of the intestinal bypass sleeve 901 may include near
the distal opening a stiffening element 908 configured to engage
intestinal peristalsis to apply distal axial tension to the bypass
sleeve 901 and aid in deployment and extension of the bypass sleeve
901 into the intestine. In alternate embodiments, stiffening
element 908 may be configured to also prop open a portion of the
sleeve 901 and locally maximize its cross-sectional area. The
stiffening element 908 may be heatstaked to the sleeve 901, insert
molded with the sleeve, bonded with adhesive or may employ any
suitable attachment technique.
[0089] FIGS. 10A, 10B, and 10C depict an embodiment of an
intragastric anchor implant 1000 with a sliding seal 1004
configured to directly support the proximal opening of an
intestinal bypass sleeve 1001. The sliding seal 1004 in this
embodiment may include an expandable sleeve support 1005 configured
to expand radially from a collapsed configuration to an expanded
configuration, the support slidably coupling the proximal sleeve
opening against an anatomical lumen wall when in the expanded
configuration. The expanded sleeve support 1005 creates a
substantially continuous circumferential seal that causes most
nutrients and food particles exiting the stomach to proceed down
the lumen of the intestinal bypass sleeve. The expandable sleeve
support 1005 may include a sinusoid, diamond, multi-link, or any
suitable expandable ring configuration. The expandable sleeve
support may be coupled to a rigid element 1002 via struts 1006,
fins, or other suitable connecting structures. In a preferred
embodiment, flexible struts 1006 connect the rod to at least one
apex of an expandable sleeve support sinusoid ring such that the
struts to allow the sinusoid to expand and compress radially while
maintaining a connection to the rigid element 1002. In a more
preferred embodiment, the struts 1006 retain a distal slope such
that an expanded sleeve support distal to a narrowed section of
lumen such as a sphincter may be radially compressed by withdrawing
the rigid element 1002 proximally such that the struts press
against the narrowed lumen and flex radially towards the rigid
element, drawing the sleeve support inward. The proximal end of the
rigid element 1002 may include an atraumatic proximal feature 1003
with an enlarged radius of curvature configured so as to provide a
blunt, atraumatic surface. Although the embodiment shown in FIGS.
10A and 10B depicts an intragastric implant 1000 in which rigid
element 1002, proximal 1003 atraumatic fixture, struts 1006 and
expandable sleeve support 1005 are a single-piece structure made of
a single material such as polypropylene or fluoropolymer, alternate
embodiments may include multiple components made of different
materials such as struts or an expandable sleeve support made of
nickel-titanium or stainless steel alloy. Fabricating the anchor
implant from a single-piece of material is advantageous as it
allows the implant to resist wear, breakage and fatigue from the
cyclical movements exerted on the anchor implant by gastric
motility over the life of the implant while also reducing its
manufacturing cost.
[0090] FIG. 10C depicts an embodiment of an intragastric anchor
implant whereby the expandable sleeve support includes tabs 1007 to
which the proximal opening of intestinal bypass sleeve 1001 may be
attached via thermal bonding, riveting, clamping, heats taking,
gluing, or other suitable means of attachment.
[0091] FIGS. 11A and 11B depict an alternate embodiment of an
expandable sleeve support 1100 includes struts 1104 and 1105 angled
in opposite directions connecting the rigid element 1102 to
alternating expandable sleeve support 1106 sinusoidal troughs. This
configuration allows expansion of the sinusoidal ring without
translation relative to the rigid element which is advantageous in
that relative to other embodiments it reduces the overall length of
the expanding support.
[0092] Drawstrings are commonly employed in removable stents as a
means of compressing the stent diameter such that it may be
withdrawn from an anatomical lumen. As depicted in FIGS. 11A and
11B, an alternate embodiment of an expandable sleeve support
includes at least one drawstring, 1107, attached to each proximal
sinusoid apex and running through at least one lateral opening 1111
in the rigid element 1102 and through a central lumen 1010. An
alternate embodiment may also include a drawstring 1108 attached to
each distal sinusoid apex and running though central lumen 1110.
Each drawstring may be withdrawn through the central lumen to
compress the expandable sleeve support 1106 by pulling on
drawstring loop 1109. The drawstring loop may be actuated by
pulling into a lumen of a support structure such as the working
channel of an endoscope, the tip of which may support the rigid
element 1102 providing a counterforce for tension on the drawstring
loop which is transmitted to and compresses the expandable sleeve
support 1106 reducing its diameter in preparation for removal of
the device from an anatomical lumen. The device may be removed by
applying a loop snare to the rigid element distal to atraumatic
proximal feature 1103,
[0093] FIG. 12 depicts an alternate embodiment of an intragastric
anchor implant 1200 including an atraumatic distal feature 1204
that includes an expandable sleeve support 1205 to which intestinal
bypass sleeve 1201 is attached. In a preferred embodiment, the
distal atraumatic feature 1204 and expandable sleeve support are
made of flexible polymer as a single piece and the expandable
sleeve support 1205 is configured to collapse and compress when the
anchor implant is proximally retracted and withdrawn from a luminal
narrowing such as the pylorus. The feature and sleeve support may
be made of silicone, polypropylene, thermoplastic elastomer such as
Santoprene, silicone, fluoropolymer, or any suitable flexible
material. In an further preferred embodiment, the distal atraumatic
feature 1204 includes radial fins 1206 or struts which are sized to
interfere with the lumen into which the feature is placed.
[0094] FIG. 13 depicts an alternate embodiment of an intragastric
anchor implant 1300 in which an expandable sleeve support 1305 is
flexibly attached to distal atraumatic feature 1304 via a flexible
coupling section 1306. The expandable sleeve support 1305 slidably
couples with an anatomical lumen such as the intestine to form a
sliding seal and, with the flexible coupling section, guides food
particles into intestinal bypass sleeve 1301 while allowing rigid
element 1302 with attached proximal and distal atraumatic features,
1303 and 1304 respectively, to move relatively freely with respect
to the expandable sleeve support 1305 in response to gastric and
intestinal motility. Expandable sleeve support 1305 may be made of
nickel-titanium alloy, stainless steel, polymer such as
polypropylene or fluoropolymer, or any suitable material. Flexible
coupling section 1306 may be made of polymer film such as
polypropylene or fluoropolymer, or elastomer such as silicone or
thermoplastic elastomer such as Santoprene. An embodiment of the
intragastric anchor implant, as shown in FIG. 13, may include a
drawstring configured to radially compress expandable sleeve
support 1305. A preferred drawstring embodiment may be configured
similarly to drawstring 1107 in FIG. 11A such that the drawstring
is directed through a lumen in the rigid element 1302 such that the
expandable sleeve support 1305 may be radially compressed by
pulling the drawstring from a point on the anchor implant proximal
to the pylorus. This method of compressing an expandable sleeve
support distal to a narrowed section of anatomical lumen such as
the pylorus is advantageous in that no additional compression aid
need be passed through the pylorus in order to collapse and
withdraw the device.
[0095] FIG. 14A depicts an embodiment of a parallel endoscopic
delivery system 1400 for deployment of an intragastric anchor
implant, in accordance with many embodiments. The delivery system
1400 is advanced into the stomach in parallel with an endoscope
1401, which is placed into a long position along the greater
curvature of the stomach. Endoscope connector 1402 attaches the
delivery system to the distal end of the endoscope via an elastic
loop into which the endoscope tip has been inserted. The endoscope
connector 1402 may be made of thermoplastic elastomer, silicone,
polymer, or any suitable material. A delivery enclosure 1403
contains an intragastric anchor implant 1407 with an attached
intestinal bypass sleeve 1406 compressed axially and radially and
contained within the delivery enclosure 1403. The delivery
enclosure 1403 is located distally to endoscope connector 1402 such
that it may be visualized through the endoscope as the entire
assembly is advanced and the delivery enclosure 1403 is placed
through the pylorus. In a preferred embodiment, the delivery
enclosure includes an optically transparent or translucent wall
such that the implant itself is visible to the endoscopist as it is
advanced and deployed. Parallel placement of the endoscope and
delivery enclosure 1403 allows continuous visual monitoring of the
intragastric anchor implant is as it is delivered and deployed. A
flexible pushrod 1404 runs through a housing 1405 and is used to
transmit axial force to push the intragastric anchor implant 1400
out of deliver enclosure 1403, deploying it into the duodenum and
stomach.
[0096] As shown in FIG. 14B, deployment of intragastric anchor
implant 1407 through parallel endoscopic delivery system 1400 may
proceed with advancement of pushrod 1404 so that bypass sleeve 1406
is advanced out of delivery enclosure 1403. The endoscopist may
advance the bypass sleeve 1406 in increments, viewing progress
through endoscope 1401, allowing intestinal peristalsis to engage
and extend the sleeve 1406 distally within the duodenum and
jejunum. Bypass sleeve extension may be confirmed fluoroscopically
or radiographically. As shown in FIG. 14C, the anchor implant's
distal atraumatic feature 1408 may be advanced out of the deliver,
enclosure and expanded once the bypass sleeve 1406 has completed
its distal extension. The delivery system 1400 and endoscope 1401
may then be withdrawn while pushrod 1404 is advanced further to
deploy the anchor implant's proximal atraumatic feature 1409. Full
and correct deployment may be confirmed endoscopically before the
endoscope 1401 and delivery system are withdrawn from the patient's
gastrointestinal tract.
[0097] FIGS. 15A, 5B, 15C, and 15D depict an embodiment of an
alternate, coaxial, delivery system 1500 for an intragastric anchor
implant in which an endoscope 1501 with an overtube 1502 including
distal balloon 1503 is delivered into the stomach and inserted
through the pylorus. As shown in FIG. 15A, the endoscope is
initially inserted into the stomach orally and its tip 1507 is
guided through the pylorus and into the duodenum while the overtube
1502 remains positioned proximally to the pylorus. The overtube
1502 is then slid distally over the endoscope through the pylorus
and distal balloon 1503 is inflated distal to the pylorus as shown
in FIG. 15B. The endoscope 1501 is then withdrawn and overtube 1502
is partially withdrawn as shown in FIG. 15C placing the stomach and
the overtube 1502 into a relatively straightened position, thus
reducing the radius of curvature of the overtube. A straighter
overtube 1502 may be advantageous in reducing the force required to
advance an intragastric anchor implant through the overtube's
central lumen. Intragastric anchor implant 1504 with intestinal
bypass sleeve 1505 is introduced into the proximal opening of
overtube 1502 and advanced distally in a compressed configuration
while the endoscope 1501 is reintroduced and is used to advance the
anchor implant. In a specific embodiment of the delivery system, a
pushrod 1508 may run through the endoscope's tool channel 1506 and
frangibly engage the anchor implant so as to enable the endoscopist
to advance the anchor implant while maintaining a relatively steady
endoscope position. The pushrod 1508 may also be advantageous in
maintaining a physical space between the anchor implant and the tip
of the endoscope which may aid in anchor implant deployment by
enabling advancement of the implant separate from advancement of
the endoscope 1501 as shown in FIG. 15D and by enhancing visibility
through the endoscope. FIG. 15D depicts an intragastric anchor
implant 1504 partially advanced out of overtube 1502 such that
intestinal bypass sleeve 1505 has become uncompressed and has
extended distally into the intestine and compressible ring 1510 has
expanded into the expanded configuration, no longer constrained by
the overtube 1502 in the constrained configuration. In the expanded
configuration, compressible ring 1510 is in substantial apposition
and sliding contact with the lumen of the duodenum Fluid such as
water or saline may be flushed through the endoscope or overtube to
aid in the extension of the bypass sleeve. A radiographic contrast
agent such as barium may be included in the fluid to aid in
fluoroscopic visualization of sleeve extension. Some embodiments of
the intestinal bypass sleeve may include stiffening element 1509
near the distal opening, the stiffening element configured to
engage intestinal peristalsis to apply distal axial tension to the
bypass sleeve 1505 and aid in deployment and extension of the
bypass sleeve into the intestine. In alternate embodiments,
stiffening element 1509 may be configured to also prop open a
portion of the sleeve 1505 and locally maximize its cross-sectional
area. Stiffening element 1509 may be configured for substantial
radiopacity such that full sleeve extension may be confirmed
fluoroscopically and may include barium, tantalum, gold, metallic
particles, or any suitable radio-opaque material in its
construction. The stiffening element 1509 may be heat staked to the
sleeve, thermally bonded with the sleeve, insert molded with the
sleeve, bonded to the sleeve with adhesive or may employ any
suitable attachment technique.
[0098] FIGS. 16A, 16B and 16D depict an alternate delivery system
1600 for an intragastric anchor implant 1602 in which a flexible
sheath 1603 encloses a compressed anchor implant and intestinal
bypass sleeve 1605. An endoscope is initially placed into the
duodenum and a guidewire 1601 is advanced distally into the
duodenum and jejunum through the endoscope's working channel per
standard endoscopic practice. As shown in FIG. 16A the flexible
sheath may be delivered over guidewire 1601 and may include an
introducer tip 1604 whose distal end tapers to a relatively small
diameter, preferably approximately to the diameter of the
guidewire, to ease passage through narrowed lumens such as the
pylorus. The guidewire may pass through the introducer tip 1604,
through the intestinal bypass sleeve 1605 and compressible ring
1611, and through the central lumen of the flexible sheath and
through the lumen 1608 of the plunger 1606 such that the entire
assembly may be advanced over the guidewire 1601.
[0099] As shown in FIG. 16B, the introducer tip 1604 may include at
least one split 1609 along a portion of its length such that it may
expand radially to allow the anchor implant to exit when advanced
distally relative to the introducer tip. The split may be held
together with a tether 1607 such as suture, monofilament, wire, or
the like, threaded through openings 1610 along adjacent edges of
the split such that removal of the tether allows the introducer tip
1604 to open and expand. Alternately, the split may be held
together with frangible connections such as perforations, scoring,
thermal bonds, adhesive, or any suitable connection means. In some
embodiments, the introducer tip may be larger in diameter than the
flexible sheath 1603, such that it may help to retain the sheath's
position within the gastrointestinal tract when fully advanced past
a narrow section of lumen such as the pylorus. When advanced
relative to the flexible sheath 1603 plunger 1606 transmits axial
force to the anchor implant to advance it distally and deploy it.
The plunger may include a lumen 1608 along a portion of its length
through which a guidewire 1601 extends.
[0100] As shown in FIG. 16C, split 1609 in introducer tip 1604 is
disconnected such that it may expand radially when tether 1607 is
withdrawn relative to the flexible sheath 1603, allowing
compressible ring 1611 to expand and intestinal bypass sleeve 1605
to expand radially and to longitudinally extend along and over
guidewire 1601. The flexible sheath and introducer t may be
withdrawn over plunger 1606 to fully release intragastric anchor
implant 1600, leaving the guidewire temporarily in place while
intestinal peristalsis applies distal axial tension to the bypass
sleeve and extends it to its full length. The presence of the
guidewire during bypass sleeve deployment may be advantageous in
preventing kinking and longitudinal folding.
[0101] FIG. 17A depicts an intragastric anchor implant 1700
supporting a pH sensor 1701 in the small intestine. A flexible
tether 1702 may connect to rigid body 1703 and extend distally to
support the sensor near the ampulla of Vater which terminates the
pancreatic and bile ducts. Alternately, the sensor may be supported
in the stomach, the duodenal bulb, across the pylorus, or jejunum.
Sensor 1701 may be a pH sensor, ultrasound transducer,
electrochemical sensor, microfluidic sensor, optical sensor,
camera, or any type of diagnostic or data-capturing apparatus. The
anchor implant may include a battery to power the sensor, power may
be provided inductively from outside the body, or power may be
generated within the anchor implant by harvesting mechanical
displacements imparted by gastrointestinal motility with
piezoelectric or electroactive elements included in the anchor
structure. The sensor may capture data to internal memory or may
transmit data externally. Alternate embodiments may be configured
to support stimulators, pacing leads, drug delivery devices, or any
other diagnostic or therapeutic devices. Embodiments supporting
drug delivery devices are particularly advantageous as certain
drugs, including some anti-obesity drugs, are much more effective
when delivered directly to the duodenum. In one embodiment of
intragastric anchor implant 1700, distal atraumatic feature 1704
includes at least one compliant helically-curved element which may
be constrained into a small-diameter configuration collinear with
the rigid element 1703.
[0102] FIG. 17B depicts an intestinal sensor with a sliding
apposition structure 1712 supported by an intragastric anchor
implant 1710, the anchor implant having a rigid member 1717 with a
distal feature 1718. The sensor 1711 is attached to the distal end
of a tether 1716 coupled to the distal feature 1718. The sliding
apposition structure 1712 provides a gentle expansion force via at
least one radially compliant element 1713 to allow atraumatic
sliding along a luminal wall so as to reduce the possibility of
hyperplastic tissue ingrowth, minimize pressure on healthy mucosa,
and enhance the removability of the sensor. Sliding apposition
structure 1712 may include an atraumatic beveled or rounded
proximal edge 1714 and distal edge 1715, may include a low friction
external coating such as a hydrophilic coating or parylene coating,
and may be configured for localized drug delivery through use of a
drug eluting material or coating. Sliding apposition structure 1712
may be comprised of a unitary compliant polymer or elastomer or may
include a polymer or metallic stenting structure, or may include a
fluid-filled balloon. In one embodiment, intragastric anchor
implant 1710 may include a distal atraumatic feature 1718 including
compliant loops which may be compressed radially inwards to form a
small-diameter constrained configuration.
[0103] Although the exemplary embodiments have been described in
some detail for clarity of understanding and by way of example, a
variety of additional modifications, adaptations and changes may be
clear to those of skill in the art. One of skill in the art will
appreciate that the various features described herein may be
combined with one another or substituted with one another. Hence,
the scope of the present invention is limited solely by the
appended claims.
* * * * *